Rabble-arm.



H. H. STOUT.

RABBLE ARM.

APPLICATION FILED DEC-411M3- Patented July 18, 1916.

w M M l M M M I 0 lNl/E/VTOR H/IRRXH. STOUT WITNESSES mom/5Y8 i To all whom it may concern.

- HARRY H. S'1 OUT,'OF NEW YORK, N. Y., ASSIGNOR "r0 GENERAL CHEMICAL COMPANY,

OF NEW YORK, N. Y., ACOBPORATION OF NEW YORK.

RAEBL'E-AEM.

Be it known that I, HARRY citizen of the United States, and a resident of the borough of Manhattan, city, county, and State of New York, have invented a certain new and useful Improvement in Rabble-Arms, of which the following, taken in connection with the accompanying drawings, is a specification.

, My invention'relates to roastingv furnaces,

particularly to ore-roasting furnaces of the general type shown and described in United States Letters Patent'to John B. F. Herreshoif, Number 616,926, dated January 3, 1899, and has for its object rtllB production of rabble arms and securing means for said arms of such furnaces, which, among other advantages, shall be easy of manufacture and of application to and removal from the furnace structure and shall be of particularf value in withstanding the heat and stresses of operation in the furnace.

' In the accompanying drawings which I illustrate an embodiment of my invention, 25

Figurel shows-such embodiment in long1 'tudin'al ve'rtical'section, and Fig. 2 is'a cross section thereof on the line 2 -2 of Fig. 1.

The central rotatable shaft of the furnace is formed in any suitable manner so as to have a central passage and an annular passage surrounding said central passage. Where my rabble arm is to be applied to the central shaft, the latter is provided with apertures in the inner wall 3 inclosing the central passage and the outer wall 4 inclosing the annular passage. These apertures are re spectively preferably surrounded anddefined by annular flanges 3" and 4tand are of a contour to correspond with the outer contour of the portion of the arm members adapted pm from the'opening' 1n the armmember 5 to be-inserted into them solthat the external arm member 5- will fit nicely' within the flange 4 and the internal arm member 6 wardly from the rotaryshaft so as tosweep over the furnace, hearth-below the. arm,,the

internal member being within the external serted and withdrawn.

T01 position and secure'thearmproperly, 100

Specification of Letters Patent. Patented J 1113 18, 1916.

Application filed December 4, 1913. I Serial No. 804,559. I

substantially its entire length.

' Both the internal and external members are preferably cylindrical pipes of wrought iron or steel, the former being of a diameter slightly greater than the radius of the latter.

The external tube 5 is provided at its outer I 5 -'member and being supported thereby along y H. S'ro 'r, a'

end with a closure 7 which may be of any not secured together but are independent of each other. Thus the external memberv may expand without affecting the internal member in any way and the stop 8 thereon is so positioned that the internal member while free to move is prevented from'slipping out .of its joint. v i

' The flange 4 is provided with anopening in its upper portion and theexternal tube 5 is provided with a-corresponding opening near itsjinne'r' end adapted to be placed in alinement'with the openingin the flange. When so positioned a lock pin 9 is inserted into the openings so as to lock the arm and the rotary shaft in .proper relationship. The pin 9 is providedwith ahead 9' of a larger'diameter than the pin shank and With a stop I I head, .to limit the movement of the pin into the openings and to provide a space-between the he'ad'9 and-the flange Pinto which shoulder 9', at a, distance vfrom the space the end of a suitable tool may be in- Y serted for "the pur 'ose of withdrawing the and thus permit of'the removal of the arm faces for engaging the underside of the head 9' and may be of such a length as to be operated through the usual furnace doorfrom therotary shaft; This I tool may be "provided with a claw endhaving cam sur- I waysthrough which the rabble arms j-areiin the shaft is rotated until the apertures therein are opposite one of the furnace doorways. The external member 5 of the arm, carrying the internal member 6 thereof, is moved through the doorway and the inner ends of the members 6 and 5 are moved into position within the flanges 3 and 4: respectively. Of course, the member 6 may be inserted before and independently of the member 5. The pin 9 is now placed in the opening of the flange d and the member 5 is rotated until the opening therein alines with the flange opening and the pin 9 drops into place. For the purpose of facilitating the process of assembling, the riveted end of the rod 8 and the opening in the member 5, are preferably located in the same diametral plane so that the openings in the flange 4 and the member 5 may be readily placed in alinement by rotating the member 5 until the visible end of the rod 8 alines with the pin 9.

The external member of the arm may be provided with -,rabble teeth in any suitable fashion so that during the rotation of the shafts the teeth will agitate and propel the material on the hearth. For cooling the rotary system, a cooling fluid such as air, is caused to traverse the central shaft and the rabble arms. The cooling medium is preferably forced into the axial chamber of the shaft formed by the wall 3, from which it passes through the arm member 6 and from the outer end of this member into the end chamber 10 of the external arm member 5; from this chamber the fluid passes through the member 5 outside of the member 6 and is discharged therefrom into the annular chamber of the shaft between the walls 3 and 4 thereof.

The rod '8. is of relatively small size and the chamber 10 is of large capacity; moreover, the capacity of the inner member is substantially the same as that of the effective portions of the external member. The result is that a large volume of cooling fluid moves with a substantially constant velocity through the arm without being obstructed to an appreciable extent. In this way a maximum volume of fluid traverses the arm and a maximum cooling is, effected. The

wrought iron or steel pipes constituting the arm are stronger and lighter and less frangible than the usual cast iron arm and so are less apt to become broken or bent during the operation of the furnace.

The removal of the arm members is easily accomplished by drawing up the pin 9 and then pullin the members out of their sockets. It wil be readily seen that even when the members have become bent, their removal is equally easy; this would not be the case if the olnts were, for example, screwmenses threaded instead of telescopic. The joints between the pipes and the shaft flanges are loose joints of extremely simple construction, the meeting surfaces of these parts being merely machined so as to have an easy fit. By reason of the fact that the arm is composed of separate members which are not bound together at any point, these members are free to expand relatively to each other without danger of shearing. Moreover in case the external member in some way becomes useless, as when it is worn out, a new member can be substituted for the old one without disturbing the internal member.

ll cla im:

1. In combination, a double-walled shaft, a rabble arm comprising external and internal pipes, the internal pipe being of a diameter greater than the radius of the external pipe and being located in and supported substantially along its entire length by the external pipe, the inner end of the internal pipe being connected with the inner wall of the double-walled shaft by a telescopic joint and the delivery end of the internal pipe being located adjacent to the outer end of the external pipe, and a stop to prevent outward movement of the internal pipe as a whole.

2. A rabble arm construction comprising an external member, an internal member independent of said external member, the outer end of said internal member being spaced from the outer end of said external member, and a stop connected with said external member to limit the outward movement of said internal member relatively to said external member.

3. In combination, a double-walled shaft, a rabble arm comprising an external member connected with one of the walls of said shaft by a telescopic joint, an internal mem ber connected with the other of said shaft walls by a telescopic joint, said internal member being movable independently of said external member and the outer end of said internal member being spaced from the outer end of said external member, and a stop connected with said external member to limit the outward movement of said internal member relatively to said external member.

4:. In combination, a double-walled shaft, a rabble arm comprising an external member connected with one of the walls of said shaft by a telescopic joint, the portions of said shaft and said member constituting such joint being provided with alined openings, a pin extending into said openings to secure said shaft and said member together, an internal member connected with the other wall of said shaft by a telescopic joint, said in- 125 ternal member being movable independently of said external member and the outer end of said internal member being spaced from the outer end of saidexternal member, and a stop connected with said external member to limit the outward movement of said internal member relatively to said external member.

Witnesses.

HARRY H. STOUT. Witnesses FRITZ ZIEGLER, Jr, GEORGE DU BoN. 

